Sclerosis of the liver accompanied by hydropericardium of long standing was observed in turkeys fed rapeseed products for 16 weeks. Histologically, extensive increases of fibrous tissue composed predominantly of reticular fibres and centrilobular degeneration of parenchymal cells were the main pathological features. Neither prominent fatty degeneration nor the formation of pseudolobules was observed. The birds fed rapeseed products for four and 12 weeks showed continuing occurrence of multiple focal and/or solitary hepatocytic necroses preceding the process of fibrosis in the livers. Glucosinolates and their hydrolytic products were considered the most likely causative factors for the hepatocytic necrosis.